# Formatting your contact numbers

The E.164 format should be used for all recipient numbers to make sure that we can send your SMS to the right receiver. Below we will explain some more about the E.164 format and how this should be used.

* [How can I use E.164 format? ](#h_01FDSNC2M3BAGH02M4CK0BH3G3)
* [Local vs. International format](#h_01FDSNC5XHA70D2B8DWT48C9HJ)

**Please note** if you do not follow this format, you might end up sending or calling the wrong country. MessageBird does not check the validity of numbers for you. Make sure the mobile phone numbers you enter are correct and valid, otherwise you may have unnecessary costs.

### Local vs. International format <a href="#h_01fdsnc5xha70d2b8dwt48c9hj" id="h_01fdsnc5xha70d2b8dwt48c9hj"></a>

When you are sending SMS or calling from your own phone to a local number, you do not need to add a country prefix to make sure your action is successful. When sending a message or calling with Messagebird, you should always make sure your numbers are internationally formatted, as in the example below:

* US number (214)-123456 with country code +1 should be entered as **1214123456**
* UK number 020-12345678 with country code +44 should be entered as **442012345678**
* Dutch number 06-12345678 with country code +31 should be entered as **31612345678**

### How can I use the E.164 format?  <a href="#h_01fdsnc2m3bagh02m4ck0bh3g3" id="h_01fdsnc2m3bagh02m4ck0bh3g3"></a>

A number in the E.164 format can have a maximum of 15 characters and consists of the following:

* International country calling code
* Local area code
* Local phone number

Depending on the destination country, phone numbers will have varying lengths. Below we have a few examples to illustrate how the numbers in E.164 format are structured:&#x20;

**1214123456**

* **1** is the country code
* **214** is the local area code for Dallas, Texas
* **123456** is the local phone number

**442012345678**

* **44** is the country code
* **20** is the local area code for London
* **12345678** is the local phone number

**31612345678**

* 31 is the country code
* 6 is the local area code, in this case the area is 'mobile'&#x20;
* 12345678 is the local phone number

If you want to add the country codes to all the numbers in your excel file in one go, you can find  [advice on how to do it here.](https://www.extendoffice.com/documents/excel/3287-excel-add-area-code-to-phone-number.html#a1)